The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the inventors hereof, to the extent the work is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted to be prior art against the present disclosure.
This disclosure relates to a method and system for reading and writing data in an arrangement of tracks on a storage medium that is written and read by a head that moves relative to the surface of the storage medium. More particularly, this disclosure relates to a control interface for such a storage medium that facilitates compensating, during operation, for contributions to the signal from an adjacent track or tracks.
In magnetic recording, as one example of a type of recording in which reading and writing are performed by a head that moves relative to the surface of the storage medium, data may be written in circular tracks on a magnetic disk. In some magnetic recording systems, track pitch was limited by the write head width. The read head was designed to be narrower than the write head so that reading can occur without picking up signals from any adjacent track. In addition, guard bands—empty bands on either side of each track—were provided to help prevent cases where data on one track are overwritten during writing of an adjacent track because of write head positioning errors.
In order to increase recording densities, track pitch has been decreased and the guard bands between the tracks have been reduced or removed, to allow more tracks to fit on the recording medium. For example, in Shingled Magnetic Recording, the tracks are written so that one track partially overlaps the previous track. In such a system, track pitch theoretically may be arbitrarily small. However, if track pitch is narrower than the read head width, then the read head may pick up a significant amount of signals from one or more adjacent tracks, leading to low data reliability.
Therefore, in order to further reduce the track pitch, it is necessary to mitigate the interference picked up from adjacent tracks during a read operation. If the component of the adjacent track picked up by the read head is sufficiently small, it may be possible to use knowledge of the data written on the adjacent track to carry out inter-track interference (“ITI”) cancellation.